According to witnesses, Rapoza kept repeating, “My foot was stuck” after he was rescued.

Investigators have not said why they think Rapoza may have tried to kill his family and himself, but have noted past cases of alleged domestic violence between Rapoza and his wife.

Rapoza has a history of mental illness, according to past arrest warrants, including an incident in April when police placed him in protective custody after he allegedly threatened to kill himself should his wife ever leave.

Raye Lynn died at the scene. Her daughter died Oct. 7.

Rapoza is being held without bail in San Mateo County Jail and has not entered a plea to three counts of murder, plus a special circumstance of multiple murder that could involve the death penalty.